1. Field of the Invention.
The invention relates to aqueous-based, liquid all purpose cleaners containing pine oil.
2. Description of Related Art.
Pine oil is a terpene rich oil derived from the extraction or distillation of pine wood, pine needles and/or pine cones. It is essentially the fraction between true turpentine and pine resin and is found to consist of a terpene rich oil containing a complex mixture comprising primarily terpinol, borneol, fenchyl alcohol, terpenes and other terpinols. It is desirably used in aqueous based detergent cleaners because of its pleasant odor which lingers after use and because it imparts a shine to hard surfaces after cleaning. It also exhibits a disinfectant property, particularly when used at more concentrated levels above about 10 wt. %.
Since pine oil and other terpene alcohol-based materials are poorly soluble or insoluble in water, it has been proposed in the prior art to include various polar solvents in water-based formulations to apparently enhance the miscibility of the pine oil in water, and thus enhance the stability of the composition. For example, U.S. Pat. No. 4,414,128 teaches the use of a polar solvent which is partially water soluble (up to 10% by weight-g./100 g. solution) and which contains at least one hydrophilic group such as an aromatic alcohol, ethoxylated phenol, esters of lower alcohols and lower acids and the like, alone or in combination with a non-aqueous solvent which is more highly miscible with water such as a lower alcohol or a monoalkyl ether of ethylene, propylene, diethylene or dipropylene glycol.
In addition, non-aqueous based clear liquid cleaning compositions containing pine oil or terpenes are disclosed in U.S. Pat. No. 5,308,531 which are said to remain clear liquids after dilution with water. This reference teaches that certain alkyl polyglycosides in combination with a dicarboxylic acid can be utilized as a solvent for the pine oil instead of more conventional solvents such as isopropyl alcohol or glycol ethers.
Aqueous-based pine oil cleaning formulations are specifically useful for cleaning wooden, plastic or metal household surfaces such as cabinets, floors, walls and appliances, and therefore advantageously may contain an alkyl or alkaryl amide repellent for repelling insects such as cockroaches. Suitable alkaryl amides include N,N-dialkyl toluamides such as N,N-diethyl-m-toluamide (DEET) and suitable alkamides include neoalkanamides such as methyl neodecanamide (MNDA) or methyl neotridecanamide (MNTDA). For example, U.S. Pat. No. 4,804,683 discloses in Example 8 a liquid pine oil cleaner composition containing a mixture of surfactant, isopropanol, pine oil, MNTDA, sodium sulfate and water.
However, the presence of insect repellents in such formulations containing pine oil presents additional problems with respect to the preparation of clear, isotropic aqueous dispersions which remain stable on standing, i.e., will not cloud up or separate after a period of storage.